Answer:
B) horizontal line at the world real interest rate.
Step-by-step explanation:
An open economy is an economy where goods and services are traded with the rest of the world. The net capital outflow is the money being invested overseas and it equals = national savings - domestic investment. In macroeconomics, savings = total investment.
Another way to calculate net capital outflow is:
net capital outflow = money domestic investors invest in foreign countries - money that foreign investors invest in the country.
In an open economy, the interest rate will be equal to the world's interest rate.